Roller blind tensioner



FIG. 1 is an upper perspective view of a roller blind tensioner;

FIG. 2 is a front view of a roller blind tensioner;

FIG. 3 is a right side view of a roller blind tensioner;

FIG. 4 is a left side view of a roller blind tensioner;

FIG. 5 is a bottom view of a roller blind tensioner;

FIG. 6 is a top view of a roller blind tensioner; and,

FIG. 7 is a back view of a roller blind tensioner.

Any broken lines shown in the drawings depict portions of the roller blind tensioner that form no part of the claimed design. 

CLAIM The ornamental design for a roller blind tensioner, as shown and described. 